Process of and apparatus for making clad metals.



J. 1". 11101111011. v PROCESS OF AND APPARATUS FOR MAKING GLAD METALS.

APPLICATION FILED DEC. 23, 1908. 1,004,673. Patented 0013,1911.

2 SHEETS-SHEET 1.

Inventor:

Attys ttest J. F. MONNOT.

PROCESS OF AND APPARATUS FOR. MAKING GLAD METALS.

APPLICATION IILBDYDEO. 23, 1908.

I 1 73- Patented 0013,1911.

2 SHEETS-SHEET 2.

Atty:

Attest: 1 Inventor:

UNITED STATES PATENT OFFICE.

JOHN F. MONNOT, .OF NEW YORK, N. Y., ASSIGNOR TO DUPLEX METALS COMPANY,OF

NEW YORK, 1\T.. Y A CORPORATION OF NEW YORK.

raocnss or AND APPARATUS ron MAKING GLAD METALS.

Patented Oct. 3.1911.

Application filed. December 23. 1908. Serial No. 469,016.

To allwhom it may concern:

Be it known that I, JOHN F. MONNOT, a citizen of the United States, anda resident of the city of New York, county of New 7 York, and State ofNew York, have -invented certain new and useful Processes of andApparatus for Making Clad Metals, of which the following is aspecification.

This invention relates to processes of and apparatus for producing cladmetals; and it comprises a process of producing clad metals wherein acore or base of ferrous or like metal is given a dense, cohering,impervious coating of an unlike, high-melting, ductile metal byelectrodepositing said unlike metal thereon in a molten state; all asmore fully hereinafter set forth and as claimed.

It is desirable for many purposes to secure coated metals having a baseorcore of a relatively stiff and strong metal, such as iron or steel,covered with a coating of one of the nobler metals, such as copper,silver, gold, brass, bronze, etc. In the prior art, these coated metalshave generally been produced by electrodepositing the coating metal froman aqueous solution, as b galvanically depositing copper upon iron rom acopper sulfate solution, silver from a cyanid solution, etc. Metalsthrown down under these conditions, however, do not give satisfactorycoatings for many purposes, being invariably crystalline, porous and oflittle real adhesion. In depositing copper from copper sulfatesolutionfor instance, it comes down as a coating consisting of crystals withintercrystalline lines or interstices.

In the plating operation the tendency'of course is for each succeedingmolecule of I then co-exten copper to be thrown down on a precedingmolecule rather than on the iron, and this tends to accumulate thecopper in the form of crystals with spaces or interstices between them.The coatm moreover, has butthe weakest possible a hesion to theunderlying metal and steel thus coated with copper will not standworking. In forming commercial electro-plated goods, it is thereforenecessary to produce the finished articles and then electroplate. It isnot possible to electroplate a lar e bar or billet of steel and themetals to the desired shape and size. The porous cop r coating has notsuflicient adherence to t e base to electrodeposited from aqueoussolution.

.In the prior art there have been many attempts made to produce thickcoated.articles which would ermit extension by simply casting anonerrous base metal against the base metal. These attempts however,have not been successful for the reason that there is'a pronounced lackof affinity between iron or the ferrous metal on the one hand and thecopper-like metals on the other hand, under ordinary casting conditions,so that merely casting the one against theot-her does not produce anyunion, .even if both metals be clean-surfaced during the operation,something which is diflicult to obtain under Working conditions. Thislack of afof thenon-ferrous metal, also obtains at lower temperatures,and it has therefore proved impracticable to produce any union betweensolid bodies of these metals. The ferrous and the non-ferrous metals aretoo unlike to permit of the production of any weld union between them inthe manner in which weld unions may be effected between like metals, asfor instance, iron and steel. Ihave, however, discovered that this lackof affinity between these two classes of metals which exists atcomparatively low temperatures disappears at higher, and by the use ofsundry expedients I can produce weldlike unions between these unrelatedmetals. For instance, if a non-ferrous metal be contacted with theferrous metal in a bi hly heated molten condition, several hundredegrees above its ordinary meltin or castin tem erature, it readily wetst e same an pro uces therewith a union which, after coolin the joinedmetals, closely resembles a weld union. The union between the met alsthus joined resists discovery by the action of cleaving tools, such as acold chisel, the action of violent temperature changes, as in heatingand quenching, and the action of mechanical force. It therefore is, oris finity at the ordinary casting temperature equivalent to, a weldunion. Methods of uniting these unlike metals resting upon thisdiscovery, are described and claimed in my Patent No. 853,716. Thecoating metal may be applied in 'one or more operations. A clean steelbillet may, for instance, be preliminarily filmed with a welded-oncoating of copper-by dipping into a superheated bath'of molten copper,withdrawn and covered'with a cohering (as distinguished from adhering)film of copper and subsequently have a further mass of copper castthereagainst at a more convenientcasting temperature. The copper of thesecond body will of course unite readily with the copper of thedescribed film. The whole mass of copper coating may be applied as asingle body of supermolten metal. In either operation it is notdesirable that the contact of the steel with highly heatedcopper be longprolonged since this is apt to result in alloying and contamination,both of the steel and of the copper. In practicing the operation stated,the film may be of one metal and the second body of another. Forinstance a clean steel billet may be film-coated with copper andsubsequently have silver, gold, brass, or bronze, cast thereagainst,these other metals uniting readily with copper at of union between theferrous metal 'and'the Y non-ferrous metal.

comparatively low temperatures.

In the present invention I have devised another method of producing asimilar type In making copper clad steel, this method, briefly stated,comprises producing a clean metallic surface on the object to be coated"and making it a cathode in a fused bath'containing dissolved copper, abody of copper being preferably used as an anode. The temperature ofthe-fused bath is kept above the melting point of copper so that thecopper is separated in a coalescent liquid form. The steel object whichmay be a billet, bar or wire, being a cathode does not suffer oxidationin the bath and preserves its clean metallic surface, assuming such asurface if it have it not already, and having a current passing throughit, is apparently in a different condition, chemically or physically,

4 which allows the molten copper to wet it copper of the sametemperature.

and unite with it in a way'which is apparently not practicable withordinary molten Under these conditions, the-copper thrown down by theelectric current, instead of forming distinct crystals or spaced bodiesof copperon the surface of the steel, as is apt to be the case inelectro-deposition of solid copper from an aqueous bath, spreads over itand wets the surface of the steel, forming a union therewith which isthe same as, or is equivalent to, the weld union produced by the more hihly heated or supermolten copper of the escribed invention. Without aspecial apparatus allowing the formation of a thick body of moltencopper around the steel, it is not easy in'this manner to produce thefull thickness of the coating, since from a suspended steel cathode themolten copper beyond the quantity sufficient to claimed a process ofproducing sound castings from copper and other metals which comprisescasting the molten metal through a deep body of molten flux or wipingmaterial, whereby the surface of the falling metal is wiped or washedand ,cleansed of all oxid and other impurities. In thus washing themolten metal, of course considerable oxid ofcopper dissolves. This fluxor slag washing can be usefully employed in producing coated bodies ofmetal, since the metal thus cast is clean surfaced and well,

for combination with the present method.

As stated, the flux, which may be a slag,

through which the copper is cast, dissolves considerable copper, whichcopper it readily yields uiider the influence of an electrolyzingcurrent to any suitable cathode. If, therefore, a body of suitableferrous metal be placed in asuitable moldcontained in or submerged in abody of flux or slag, holdin dissolved cop er, and the current passethrough it, using the billet as a cathode, the billet becomes coatedwith the described cohering weld film. Without removing the mold furthercopper can now be cast down per descends through the deep layer ofmoladapted for forming unions. i Such a method with certainmodifications, is well adapted ten wiping material particles of oxidupon its surface are wiped or dissolved ofl, and serve to maintain thecopper content of such flux or slag. If the billet, as is usu-.

ally the case, is contained in a mold casing,

upon pouring the copper for the cast on coating the slag is completelydisplaced and may be collected in any convenient manner and used for afurther operation.

As will be seen, in the film coating opera tion, a portion of the copperdissolved in the flux is removed and preci itated upon the billet as thefilmed layer 0 copper, 1mpoverishifig'the bath to thatextent. The coppercontent of the bath, however, is replenished in casting fluid copperthrough it,

by solution of oxid, while in turn the flux by its solvent and wipingaction cleans the copper so cast and places it in a proper physicalcondition-to unite at once in a true metallic union with the copper ofthe film coating.

Obviously, using the described process, apparatus of widely varied formmay be. employed. The mold may, for instance, be submerged in a body ofmolten flux containing copper, a billet therein filmed electrolyticallyand copper cast down throu h the flux into the mold. The necessary bodyof flux for submerging the molds may be contained on the hearth of anordinary reverberatory furnace. Using a high silica slag or flux thehearth may be sand lined.

Or a body of molten cupriferous flux or slag --may be contained in alarge crucible and a suitable mold casing containing the billet(suitable contacts bein provided) may be submerged therein ant after thefilming, copper may be cast down into the mold through the flux. Theflux in the mold displaced by the copper overflows into the outercrucible. The full amount of copper for the coating may be producedelectrolytically, but in such case suitably shaped apparatus must beused adapted to maintain a layer of fluid copper. For instance, a twopart casing may be employed, this casing being adapted to contain a deepbody of melted flux and bein divided by a low vertical wall, terminatingbelow. the surface of the flux, into two compartments. In the onecompartment, which is a mold, the billet is suitably supported to give aspace about it for the requisite layer of molten cop er. In the othercompartment is a body o molten copper. Upon now making the billet acathode and the body of copper an anode, copper will be transferred fromthe anode to the cathode and, being molten when-deposited, will fill thespace about the billet. In all these operations the iron being acathode, any oxid upon its surface will be reduced and a clean surfaceof iron automatically produced. It is always, however, well to sandblast and otherwisecleanse the billet before the operation, to removecinder, and oxid in forms which are not readily reduced.

The fused bath containing dissolved copper may be any of a number ofsubstances, its particular composition not mattering greatly. A suitablebath may be made of a mixture of silicate of soda, borax, and a littlefluorspar in which is dissolved black oxid of copper, copper millscale,etc. Or it may be any of the ordinary silicate slags. Borax may be used;fluorspar and other fluorids may be employed. During the operation thebath should be maintained at a temperature somewhat above [the meltingpoint of copper, but it need not reach .the described supermoltentemperature of copper.':A temperature of 2000- F. is suitable.

Within the vessel and surrounded by the flux is preferably placed a bodyof the coating metal, such body being, naturally, in amolten condition.This body of molten metal is made an anode. Contact therewith to formthe electric circuit may be through the walls of the vessel, where thisis made of graphite or other conductive material, or may be otherwiseproduced. The cathode is the billet, wire, bar or other body to becoated, and this cathode is dipped in, or otherwise contacted with, themolten body of flux containing dissolved copper. Under these conditions,upon passage of the current, copper deposits on the ferrous metal body,but the temperature of the'bath being above the melting point of copper,the de posit is in the liquid form. The drops of copper so producedspread over and thoroughly wet the surface of the article, unitingtherewith to form an intimate union of the character desired. A currentof about 5 volts and 20 amperes per square foot of cathode surface isfrequently suitable. If

' a steel billet or bar be so treated it may be removed from the fluxbath as soon as the deposited copper has formed a continuous filmtherefrom and may then have anydesired amount of copper cast againstthis filmed surface, either before cooling or after cooling andreheating in a mold. In reheating care should be taken to avoidoxidation of the filmed. surfaces. 'By a suitable arrangement of theapparatus, as by placing the billet in a depression, the full amountofcopper desired for the coating may be deposited thereon, but this is notordinarily desirable. Where it is desired to secure a relatively" thincoating of copper upon a wire, the wire may be simply passed through themolten flux bath, wherein it acts as a cathode, and the desired amountof copper directly attached thereto. On wires it is frequently notdesirable to have more than a thin coating or more than such as willcohere in a liquid state. After thus coating, however, it is usuallydesirable to give the render it uniform. The wire before coating may bepreliminarily heated in a lead bath or any other suitable way, as bypassingthrough hot tube, may thence be passed I through a flux bath toclean it, thereafter through the described molten copper-containing bathto give it the coating, and then cooled at little and drawn through adie. Enough copper may be deposited. very quickly by the above methodsto permit several reductions. This process is also appli-' cable to thecoatin of structural shapes,

,sheets, etc., first sca ing-either with steam or rotary:burnishingscratch brushes, and

then cleaning the'flux bath. The operation may'bethe same aswith wire;The

process is in fact applicable to all purposes in which a thin coating isto be applied to a finished article, a structural shape, for example, orto something near a finished article.

process may, as seen, be continuous, the

metal to be coated being fed continuously through the coating bath. Itmay be guided by rollers which will also form means for carrying currentto the material. The particular mechanism employed in the present'process however is not very material.

Other high-melting ductile non-ferrous metals may be united to ferrousmetals in the manner described. It is, however, somewhat troublesome soto apply gold and silver owing to the difficulty of securing baths ofthese two metals which will stand very high temperatures. With a bath offluorspar containing some calcium chlorid however, and an anode ofsilver or gold, enough metal will dissolve in a fused bath to permitdeposition. The process is, however, more particularly applicable tocopper. Aluminum may also be advantageously deposited in a similarmanner, using a bath of fused fluorides or the like and replenishing thealuminum content by additions of bauxite or other form of alumina. Moresimply, a fused anode of aluminum may be employed.

In the accompanying illustration I have shown more or lessdiagrammatically sundry apparatus of the many types adapted .35 for usein the described process.

In said drawings: Figure 1 shows a central vertical sectionof apparatusadapted for use for coating wire and like flexible material. Fig. 2shows a central vertical section of apparatus for coating billets andthe like. Fig. v3 shows a central vertical section of apparatus forcoating large billets, the same being supported horizontally. Fig. 1shows a. perspective elevation of a billet such as shown in Fig. 3. Fig.5 shows a detail perspective view of one of the refractory-coveredspacing pieces 18.

Referring first to Fig. 1, 1 designates a crucible, the main portion ofwhich is contained within a furnace 2 provided with suitable heatingmeans, for example, a liquid fuel burner '3. This crucible is providedwith a cover 4 having in it'suitable openings 5 and 6 for the entry andexit .of the wire or the like to be coated. In the crucible is a body ofmolten fiux'7 and beneath it. a body of molten coating metal 8. Thecrucible is supposed to be constructed of some electrically conductivematerial, for example, homogenized or compacted graphite. This crucibleI have shown supported upon a suitable pedestal 9 of graphite orthe likeand provided with an electric connection 10 whereby electric current maybe 6 passed through the crucible. The crucible In the case of wire rods,sheets, etc., the

cover 4 is insulated electrically from the crucible itself by insulatingmaterial 11 adapted to withstand high temperatures; for example, micainsulation. The wire to be coated, which is supposed to be drawn from asuitable source, is passed between feeding rolls 12 and 13 through aheating tube 14: and through the orifice 5 of the cover into the body offlux, and then out through the sizing die 15 to carrying ofi rolls 16and 17; the wire forming a loop within the crucible. I have indicateddriv-' ing means for rolls l2 and 16, comprising a shaft 18 driving roll12' by bevel gears 19, said shaft also carrying a friction roll 20working against the face of roll 16 as a friction disk, so as to drivesaid roll, this friction roll 20 being movable toward or from the centerof roll 16 by a suitable lever 21, so that the speed of drive of roll 16may be regulated as necessary to preserve the loop of the Wire in thecrucible.

The crucible cover may be provided with a downward projection 22 whichinsures that a sufficient length of the wire shall re: main immersed inthe flux; any tightening .of the wire due to contact with thisprojection being immediately observable to the operator, who will thenregulate the rate of drive of roll 16 so as tomaintain a loop of lengthsufficient to clear projection 22.

Suitable means are provided for connecting the wire to the electriccircuit; for example, one conductor 23 of the circuit, may beelectrically connected to shaft 18, the other conductor 24 beingconnected to the terminal 10 of pedestal 9. 25 designates a suitableelectric generator.

The voltage of current used will ordinarily below and the currentdensity comparatively high. The current may, for example, be of fivevolts and of ten to twenty amperes per square foot of surface of metalwithin the flux. Through the pipe 14 a suitable heated gas, for example,hot producer gas, may be passed to initially heat the wire. In carryingout the process with this apparatus the Wire, fed forward by rolls 12and 13, and initially heated in tube 14, passes into the flux bath andthere has deposited upon it molten copper which combines with thesurface 'of the wire to form a coating,.the thickness of this coatingbeing determined by the sizing die 15 through which the wire passesimmediately after emerging from the flux, being then fed off by rolls 16and 17. After passing from the sizing die the wire may pass through atube 26 containing cold producer gas or other non-oxidizing atmosbody ofmolten coating metal 33 and resting upon a pedestal 34 forming oneterminal of;

an electric circuit; the porter bar 29 forming another terminal of thiscircuit as indicated.

The billet 27 may have been preheated, and to avoid oxidationfof itssurface prior to contact with the flux, the mold casing 28 may containproducer gas or like protective atmosphere supplied through a pipe 35,all as described in my Patent No. 853,716. 36 designates a suitablehoist by which the billet and the mold casing may be lowered or raised,together or separately, as desired.

The cover 37 of'crucible 31 having been removed, the billet 27 islowered from the easing into the flux 30, for a sufiicient time topermit the deposition of the desired coating on the surface of thebillet such coating being electrodeposited, as previously described. Thebillet is then withdrawn into the mold casing 28, oxidation of the filmcoating being prevented by the non-oxidizing atmosphere in said moldcasing, and the mold casing is then moved over another crucible 38contained in furnace 32, which crucible contains molten coating metal,cop per for example, this body of molten. metal being at about ordinarycasting temperature.

A bottom plate 39 is applied to the mold casing and the casing with thecoated billet within it is then lowered into the molten metal incrucible 38 until the openings 40 in the sides of the mold casing aresubmerged in the molten metal; a strip of suitable closing material 41(asbestos paper or the like is a suitable material) which heretofore hascovered said openings, being stripped off just before this portion ofthe casing passed into the crucible; the molten metal then fills thecasing, forming a cast-on coating which unites with the film coatingalready formed on the billet 27.

Further quantities of copper or other coating metal may be supplied tothe crucibles 31 and 38 from time to time, through the open tops ofthese crucibles; the metal supplied to crucible 31 may be coppermillscale and the like (black oxid of copper) or may be copper filings,turnings, chips, etc. The copper supplied to crucible 38, shouldpreferably be melted and then supplied to the crucible in the moltencondition.

In the form of apparatus shown in Fig. 1, the cover 4 may be providedwith a charging opening 42, through which fresh quantities of coatingmetal may be supplied from time to time.

In the form of apparatus shown in Fig. 3, I have indicated a furnace 43of the reverberatory type, adapted to be heated re- I generatively orotherwise, as desired, and

provided with a deep hearth 44 adapted to I contain the mold '45together with a body, of

flux or slag 46 sufficiently deep to completely submerge the mold. TheInold 45 rests upon a pedestal 47 forming an electric terminal. Saidmold is first placed on the hearth, being submerged in the flux, andbeing held down in any suitable manner, and within it are placedsuitable spacing pieces 48 to support the billet the desired distanceabove the bottom of the mold. These spacing pieces may for example, beiron bars covered with fire clayor other suitable material to preventthem from acting as electric conductors, although it is not material ifsome" electric current be transmitted through these spacing pieces tothe billet to be coated, since the voltage of the current used is lowand the area of contact of these spacing pieces with the billet issmall.

The billet to be coated, 49, is lowered into the mold 45 through asuitable opening 50 in the roof of the furnace, and as it enters saidcrucible it displaces part of the flux previously within the mold,theflux so displaced flowing out into the main body of flux in the hearthof the furnace. The elec-' tric current passing from the terminal 51through the mold and flux still within the mold, to the billet, causesdeposition on the film coating already formed on' the surface of thebillet.

The hearth of the furnace may be a sand hearth, such as is well known infurnace practice, if the slag used be one high in silica; and therebywaste of electric current is avoided.

Since copper and like metals sometimes tend to deposit unevenly uponiron and steel, the article to be coated may be dipped in a solution ofcopper sulfate or other suitable salt, to give it a thin or strikingcoating of chemically-deposited metal, and then a further coating may bedeposited in the flux bath, as above described.

That I claim is 1. The process of providing one metal with a cohering,dense,-impervious coating of another metal which comprises making ahigh-melting metal body a cathode in a bath of fused electrolytecontaining a dissolved bath being maintained at a temperature above thenormal melting point of such high-melting dissolved metal.

2. The process of providing ferrous metal with a cohering, dense,impervious coating of co per which comprises making a ferrous metal bodya cathode in a bath of fused electrolyte containing dissolved copper,such bath being maintained at a temperature above the melting oint ofcopper.

3. The process of providing ferrous metal with a cohering, dense,impervious coating of cupriferous metal which comprises making a ferrousmetal body a cathode in a bath of fused electrolyte containing dissolvedcupriferous metal, such bath being maintained at a temperature above themelting point of such cupriferous metal.

4. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal which comprises placing the ferrousmetal in a bath of fused electrolyte containing a dissolved ductilehighmelting metal and maintained above the melting point of'such metal,and passing a current until the ferrous metal becomes covered with alayer ofsuch other metal in a fluid state. I V

5. The process of providing ferrous metal with a' cohering, dense,impervious coating of copper, which comprises placing the ferrous metalin a bath of fused electrolyte containing copper and maintained abovethe meltin point of copper, and passing a current til the ferrous metalbecomes covered with a layer of copper.

6. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal, which comprises film-coating suchferrous'metal with a layer of highmelting ductile metal byelectrodeposition from a bath of fused electrolyte containing such metalin a dissolved state, and casting a further quantity of'fluid metal intocontact with the film-coating so produced.

7. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal which comprises making such ferrousmetal a cathode in a bath of a fused electrolyte containing dissolvedcopper and producing a film coating of copper thereon and casting afurther quantity of metal in contact with the filmed surface.

8. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal which comprises making such ferrousmetal a cathode in a bath of a fused electrolyte containing dissolvedcuwith a cohering, dense, impervious coating of another metalwhichcomprises making such ferrous metala cathode in a bath of a fusedelectrolyte containing dissolved copper and producing a film coating ofcopper thereon and casting a further quantity of copper in contact withthe filmed surface.

10. The process of providing ferrous metal with a cohering dense,impervious coating of another metal which comprises film-coating aferrous metal with a layer of a highmelting ductile non-ferrous metal byelectrolysis from a bath of fused electrolyte and casting fluid metalthrough such fused electrolyte into contact with the filmed surface.

11. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal which com rises film-coating aferrous metal with a ayer of copper by electrolysis from a bath of fusedeiectrolyte and casting fluid metal through such fused electrolyte intocontact with the filmed surface. I

12. The process of providing ferrous metal with a cohering, dense,impervious coating 1 of another metal which comprises film-coating aferrous metal with a layer of copper by electrolysis from a bath offused electrolyte and casting fluid copper through such fused(Electrolyte into contact with the filmed surace.

13. The process of providing one metal with a cohering, dense,impervious coating of another metal, which comprises maintaining withina suitable receptacle, a body of molten coating metal and in contactwith it, a body of fused electrolyte, immersing in such electrolyte thearticle to be coated,

formed of a metal unlike the coating metal, and making it the cathode ofan electric circuit, and passing an electric current through saidelectrolyte and cathode.

14. The process of providing one metal with a cohering, dense,impervious coating of another metal, which comprises maintaining withina suitable receptacle, a body of molten coating metal and in contactwith it, a body of fused electrolyte, immersing in such electrolyte thearticle to be coated formed of a metal unlike the coating metal, andmaking it the cathode of an electric circuit, and passing an electriccurrent through said electrolyte and cathode, thereby producing a filmcoating of the coating metal on said cathode, and then casting a furtherquantity of coating metal into contact with the filmed surface.

15. The process of providing one metal with a cohering, dense,impervious coating of another metal, which comprises maintaint triocircuit, and passingan electrlc current through said electrolyte andcathode.

16. The process of providing one metal with a cohering, dense,impervious coating of another metal, which comprises maintaining withina suitable receptacle, a body of molten non-ferrous high-melting metaland in contact with it, a body of fused electrolyte, immersing in suchelectrolyte the article to be coated formed from, ferrous metal, andmaking it the cathode of an electric circuit, and passing an electriccurrent through said electrolyte and cathode, thereby producing a filmcoating of the non-ferrous metal on said cathode, and then casting afurther quantity of non-ferrous metal into contact with the filmedsurface.

17. Apparatus for coatin metal objects comprising a receptacle havingwithin it a body of coating metal and in contact therewith, a body offused electrolyte, means for feeding metal to be coated into theelectrolyte, in said receptacle, and for Withdrawing the metal to becoated from such electrolyte, and means for passing an electric currentthrough such electrolyte to such article to be coated as a cathode.

18. The process of providing one metal with a cohering, dense,impervious coating of another metal which comprises immersing ahigh-melting metal body in a solution of a salt of an unlike metal andthereby producing a striking coating of the unlike metal, and thenmaking such metal body a cathode in a bath of fused electrolytecontaining a dissolved ductile high melting different metal, such bathbeing maintained at a temperature above the melting point of suchhigh-melting metal.

19. The process of providing ferrous metal with a cohering, dense,impervious coating of copper which comprises immersing a body of ferrousmetal in a solution of copper sulfate or other suitable copper salt andthereby producing a striking coating of copper on the ferrous metal, andthen making such ferrous metal body a cathode in abath of fusedelectrolytecontaining dissolved copper, such bath being maintained at atemperature above the melting point of copper.

- 20. The process of coating steel with copper which comprises makin asteel object a cathode in a bath of fuse cupriferous electrolytemaintained at a temperature above the melting point of copper till afilm coating of fused copper forms.

21. An improvement in the art of electroplating metals which consists inperforming the operation of electrolysis at a temperature as great asthe melting point of the metal deposited.

22. The herein described method of'electroplating which consists inheating ametalcontaining solutionto the melting point of the containedmetal, and employing such solution so heated as the electrolyte indepositing'the metal uponanother metal introduced into the cell as acathode. Y

23. The herein described method of copper plating which consists indissolving a copper salt in a flux which may be maintained in, liquidstate at the melting point of copper, bringing such solution to themelting point of copper and carrying on the operation of electrolysis atsuch tempera- ,ture.

24. The herein described improvement in the art of copper plating whichconsists in.

performing the operation of electrolysis at a temperature as great asthe melting point of copper.

25. The herein described method of coating iron with copper whichconsists in electro-plating the one metal upon the other from anelectrolyte maintained in liquid state at the melting point of the metalto be deposited.

26. The herein described method of forming and uniting bodies ofdifferent metals which consists in electro-plating a body of one metalwith the other metal from an-electrolyte maintained at the melting pointof the metal so deposited and forming upon the electro-plated surface anadditional body of the met-a1 which forms the deposit.

27. The herein described method of forming and unitin bodies ofdifferent metals which consists 1n electro-platin'g a body of the onemetal with the other from an electrolyte maintained at the meltingtemperature of the deposited metal and casting upon the surface of suchelectro-plated body an additional body of metal.

28. The herein described method of electro-plating copper which consistsin dissolv ing a copper salt in borax, raised to a temperature as highas the melting point of copper and performing the operation ofelectrolysis at such temperature.

29. The process of coating a ferrous metal which comprises depositing acoating of a metal at one temperature, then depositing a second coatingof the same metal at a different temperature, one ofthe deposits beingproduced in a fused electrolyte at the temperature of the melting pointof the metal deposited.

30. The process of coating a ferrous metal which comprises depositing acoating of copper at one temperature then depositing a second coating ofcopper at a different temperature, one of the deposits being produced ina fused electrolyte at the temperature of melting copper.

31. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal which comprises film-coating aferrous metal with a layer of copperby electrolysis from a bath of fusedelectrolyte in a deep layer, and casting fluid metal through such deeplayer of fused electrolyte into contact with the filmed surface.

32. The process of providing ferrous metal with a cohering, dense,impervious coating of another metal which comprises film-coating-aferrous metal with a layer of copper by electrolysis from a bath offused electrolyte in a deep layer, and casting fluid copper through suchdeep layer of fused 10 ilectrolyte 1nto contact with the filmed surace.

In testimony whereof I affix my signature, in the presence of twowitnesses.

JOHN F. MoNNo'r. Witnesses H. M. MARBLE, FRANK E. RAFFMA

